Used as a key building block in organic synthesis, particularly in the preparation of phosphine ligands for transition metal catalysis. Its ethynyl group enables click chemistry and Sonogashira coupling reactions, making it valuable in materials science for constructing conjugated systems in organic electronics such as OLEDs and molecular wires. Also employed in the development of metal-organic frameworks (MOFs) and catalytic systems for cross-coupling reactions due to the strong electron-donating properties of the phosphine group.